GB2374714A - :LED backlighting system - Google Patents
:LED backlighting system Download PDFInfo
- Publication number
- GB2374714A GB2374714A GB0200653A GB0200653A GB2374714A GB 2374714 A GB2374714 A GB 2374714A GB 0200653 A GB0200653 A GB 0200653A GB 0200653 A GB0200653 A GB 0200653A GB 2374714 A GB2374714 A GB 2374714A
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- Prior art keywords
- emitting diode
- light emitting
- lcd
- light
- light pipe
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Classifications
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- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/1336—Illuminating devices
- G02F1/133602—Direct backlight
- G02F1/133609—Direct backlight including means for improving the color mixing, e.g. white
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
- G02B6/0023—Means for improving the coupling-in of light from the light source into the light guide provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
- G02B6/0068—Arrangements of plural sources, e.g. multi-colour light sources
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0081—Mechanical or electrical aspects of the light guide and light source in the lighting device peculiar to the adaptation to planar light guides, e.g. concerning packaging
- G02B6/0085—Means for removing heat created by the light source from the package
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/1336—Illuminating devices
- G02F1/133602—Direct backlight
- G02F1/133603—Direct backlight with LEDs
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/20—Controlling the colour of the light
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
- F21Y2115/00—Light-generating elements of semiconductor light sources
- F21Y2115/10—Light-emitting diodes [LED]
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0013—Means for improving the coupling-in of light from the light source into the light guide
- G02B6/0023—Means for improving the coupling-in of light from the light source into the light guide provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
- G02B6/0031—Reflecting element, sheet or layer
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0033—Means for improving the coupling-out of light from the light guide
- G02B6/0035—Means for improving the coupling-out of light from the light guide provided on the surface of the light guide or in the bulk of it
- G02B6/0038—Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0033—Means for improving the coupling-out of light from the light guide
- G02B6/0056—Means for improving the coupling-out of light from the light guide for producing polarisation effects, e.g. by a surface with polarizing properties or by an additional polarizing elements
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
- G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
- G02B6/0081—Mechanical or electrical aspects of the light guide and light source in the lighting device peculiar to the adaptation to planar light guides, e.g. concerning packaging
- G02B6/0083—Details of electrical connections of light sources to drivers, circuit boards, or the like
-
- G—PHYSICS
- G02—OPTICS
- G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
- G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
- G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour
- G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour based on liquid crystals, e.g. single liquid crystal display cells
- G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
- G02F1/1333—Constructional arrangements; Manufacturing methods
- G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
- G02F1/1336—Illuminating devices
- G02F1/133614—Illuminating devices using photoluminescence, e.g. phosphors illuminated by UV or blue light
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/50—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
- H05B45/52—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits in a parallel array of LEDs
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B45/00—Circuit arrangements for operating light-emitting diodes [LED]
- H05B45/50—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits
- H05B45/56—Circuit arrangements for operating light-emitting diodes [LED] responsive to malfunctions or undesirable behaviour of LEDs; responsive to LED life; Protective circuits involving measures to prevent abnormal temperature of the LEDs
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Nonlinear Science (AREA)
- Mathematical Physics (AREA)
- Chemical & Material Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Liquid Crystal (AREA)
- Planar Illumination Modules (AREA)
Abstract
A liquid crystal display (LCD) device (100) having non-white (126) and white light emitting diodes and a liquid crystal display (104). A spectrum converting material (130) is positioned between non-white LEDs and the LCD to convert the non-white light from the LEDs toward a white light spectrum. The liquid crystal display may include a plurality of light emitting diodes, a light pipe (110), and a spectrum converting material. The spectrum converting material may be a phosphorized material located between the plurality of non-white light emitting diodes and the light pipe. A light extracting surface (120) may be located near a first surface of the light pipe, a diffuser (118) located near a second side of the light pipe, where the first and second sides are opposite sides of the light pipe, a reflective polarizer (106), and a liquid crystal display. The light from the light pipe may passes through the diffuser, the reflective polarizer, before backlighting the liquid crystal display. The non-white LEDs may include blue LED, ultraviolet LEDs, and the like.
Description
- 237471 4
- 1 - LED BACKLIGHTING SYSTEM
This invention relates generally to the field of light
emitting diode (LED) circuits. More specifically, this invention relates to the field of backlighting of liquid
crystal displays with non-white LEDs and white LEDs.
Backlighting for active matrix liquid crystal displays ("AMLCD") typically uses a cold cathode fluorescent lamp ("CCFL") device. CCFL devices tend to have high back lighting efficacies. CCFL devices have numerous drawbacks. CCFL devices may contain Mercury, a highly dangerous substance that has been banned from many AMLCD applications. CCFL devices may have poor efficacy at lower temperatures, which requires additional circuitry such as a heater element or a boost current circuit.
. CCFL devices may have a non-linear efficacy curve with respect to temperature. CCFL devices may require an inverter to drive the CCFL device. CCFL devices may require complex control schemes, including light sensors and temperature sensors to provide adequate dimming ratios for night time operations. CCFL devices may have a short life expectancy, especially at lower operating temperatures, and may require additional electro-magnetic interference ("EMI") shielding and electric filtering.
Alternatives to CCFL devices for back lighting an AMLCD include Xenonbased devices. Xenon-based backlighting circuits do not contain Mercury, have superior low temperature life expectancy and low temperature operational characteristics, and have less phosphor
- 2 degradation than CCFL devices. While Xenon lamps correct many of the problems of the CCFL lamp technology, the Xenon lamp technology creates many new problems. For example, Xenon lamps tend to be relatively expensive and require complex control circuitry. Xenon lamps have low efficacy. For example, a Xenon lamp with twice the diameter may provide only half the brightness of a mercury-based CCFL lamp. Because the efficacy of the Xenon lamp may be less than half of a CCFL lamp, the additional power needed to power a Xenon based circuit creates a problem of power consumption.
Another alternative to CCFL devices for backlighting are white LEDs. White LEDs have been used to provide light to light pipes in LCD backlighting devices. White LEDs may be more expensive than colored LEDs.
The invention provides a liquid crystal display (LCD) device having white and non-white LEDs. The non-white LEDs have a spectrum converting material between non-
white LEDs and the LCD to convert the non-white light from the LEDs toward a white light spectrum.
In one aspect, a liquid crystal display backlighting device has a nonwhite light emitting diode, a liquid crvetal display, and a phosphorized material. The phosphorized material is located between the light emitting diode and the liquid crystal display. The phosphorized material down converts light from the light emitting diode toward white light spectral radiance.
- 3 - In another aspect, a liquid crystal display device has a non-white light emitting diode, a light pipe, a spectrum converting material, a light extracting surface, an enhanced diffuser reflector a diffuser, a reflective polarizer, and a liquid crystal display. The spectrum converting material is between the non-white light emitting diode and the light pipe. The light extracting surface is located near a first side of the light pipe.
The diffuser is located near a second side of the light pipe. The first and second sides are opposite sides of the light pipe. Light from the nonwhite light emitting diode is converted by the spectrum converting material.
The light enters the light pipe and passes through the diffuser, the reflective polarizer, and then backlights the liquid crystal display.
In a further aspect, a liquid crystal display device has a light emitting diode, a spectrum converting material, a diffuser, a reflective polarizer, and a liquid crystal display. The light emitting diode emits non-white light.
Light from the light emitting diode is converted by the spectrum converting material before the converted light passes through the diffuser and the reflective polarizer, and before backlighting the liquid crystal display.
In yet another aspect, a liquid crystal display has a non-white light emitting diode, a light pipe, a light extracting surface, a diffuser, a reflective polarizer, and a liquid crystal display. The light pipe has a phosphor coating that converts the spectrum of the non-
white light emitting diodes and the light pipe. The light extracting surface is located near a first side of
- 4 - the light pipe. The enhanced diffuser reflector is located near an opposite side of the light pipe. The diffuser is located near a second side of the light pipe.
The first and second sides are opposite sides of the light pipe. Light from the light pipe passes through the diffuser and the reflective polarizer, and then backlights the liquid crystal display.
In yet a further aspect, a liquid crystal display device has a white light emitting diode, a light pipe, a light extracting surface, a diffuser, a reflective polarizer, and a liquid crystal display. The light extracting surface is located near a side of the light pipe. The diffuser is located near a second side of the light pipe.
The first and second sides are opposite sides of the light pipe. Light from the white light emitting diode enters the light pipe and passes through the diffuser, the reflective polarizer, then backlights the liquid crystal display.
Other systems, methods, features, and advantages of the invention will be or will become apparent to one skilled in the art upon examination of the following figures and detailed description. All such additional systems,
methods, features, and advantages are intended to be included within this description, within the scope of the
invention, and protected by the accompanying claims.
The invention may be better understood with reference to the following figures and detailed description. The
components in the figures are not necessarily to scale,
s emphasis being placed upon illustrating the principles of the invention.
FIGURE 1 represents a cross-sectional top view of an LCD backlighting device according to an embodiment.
FIGURE 2 represents a cross-sectional side view of the LCD backlighting device of Figure 1.
FIGURE 3 represents a top view of an embodiment of a flexible LED circuit board with top-light LEDS on two-fold tabs.
FIGURE 4 represents a circuit diagram of an LED circuit according to an embodiment.
FIGURE 5 represents an embodiment of an LCD device that includes white LEDS.
FIGURE represents another embodiment of an LCD device that includes white LEDS.
FIGURE 7 represents another embodiment of an LCD device that includes nonwhite LEDS.
FIGURE 8 represents a further embodiment of an LCD device that includes non-white LEDS.
A liquid crystal display (LCD) device with backlighting may have a reflective polarizer, backlighting light emitting diodes, a light pipe, and a liquid crystal display. Such an LCD device may be suitable for AMLCD backlighting with sufficient luminosity for day time automotive applications. The LCD device may be an AMLCD based-device. The reflective polarizer may be a DBEF-D reflective polarizer. The LEDs may be white LEDs and non-white LEDs. The non-white LEDs may be blue LEDs, ultraviolet (W) LEDs, or other colored LEDs. With non-
white LEDs, the LCD device has a phosphorized material
6 - between the LEDs and the liquid crystal display. The phosphorized material may be a phosphorized rubber or other down converting materials. The phosphorized material converts the light from the non-white LEDs to a white light. This technique allows the color coordinates of the converted light to be selectable with improved edge uniformity, cost savings, and longer LED life. Some conventional white LEDs may use a conversion phosphor layer inside the LED to convert the light coordinates to the desired white color. In one respect, the brightness ratio of white LEDs to non-white LED is about 2.5:1.
During the life time of an LED, the LED's luminance steadily degrade. Nonwhite LEDs, such as blue LEDs, degrade slower than comparable white LEDs. This can results in brighter LCD backlight over the life of the LED by using non-white LEDs and a phosphorized material.
A significant cost saving may be expected by using non-
white LEDs and a phosphorized material over comparable white LEDs devices. Color binning, which is required with white LEDs is eliminated by using colored LEDs.
Figures 1 and 2 represent an embodiment of an LCD device 100 that includes non-white LEDs and a phosphorized material. Figure 1 represents a cross-sectional top view of the LCD 100 backlighting device. Figure 2 represents a cross-sectional side view of the LCD 100 backlighting device. The LCD device 100 may have other configurations or arrangements including these with fewer or additional arrangements.
7 - Referring to Figure 1, the LCD device 100 includes a frame 102 and 114, a liquid crystal display (LCD) 104, a reflective polarizer 106, a diffuser 108, a light pipe 110, a printed circuit board 112, a circuit board 116, an enhanced diffuser reflector (EDR) 118, optional EDRs 118a, 118b, and 118c, a light extractor 120, a plurality of LEDS 126, a plurality of LED current control circuits 128, and phosphorized materials 130a, 130b, and 130c.
The circuit board 116 may be a flexible circuit board, a rigid circuit board, or the like. The plurality of LEDs 126 may include a plurality of blue LEDs, ultraviolet LEDs, other non-white LEDs, or a combination thereof.
The optional EDRs 118a, 118b, and 118c may be located between the LEDs 126 and the respective phosphorized materials 130a, 130b, and 130c. The EDRs 118a, 118b, and 118c may include apertures for the light from the LEDs 126 to shine through to the light pipe 110. The apertures may be shaped to match the active output regions of the LEDs 126. While EDRs are described, other polarization scrambling films may be used.
The phosphorized materials 130a, 130b, and 130c are located between the LEDs 126 and the light pipe 110. The phosphorized materials 130a, 130b, and 130c may include a phosphorized rubber strip. Light from the LEDs 126 passes through the phosphorized materials 130a, 130b, and 130c where a portion of the light is down converted. The down converted light that exits from the phosphorized materials 130a, 130b, and 130c has a white color coordinate. The white light from the phosphorized materials 130a, 130b, and 130c then enters the light pipe 110.
- 8 - Light that enters the light pipe 110 is internally reflected off the top and bottom surfaces. The light that strikes the top surface of the light pipe 110 at an angle less than the critical angle will pass through the front of the light pipe 110 and strike the diffuser 108.
The light that strikes the top of the light pipe 110 at an angle greater than the critical angle will be reflected in the light pipe 110. In one aspect, the light that strikes the EDR 118 passes through the diffuser reflector's first non-diffuse surface and exits the EDR surface. In another aspect, the EDR 118 scrambles the polarization and reflects the light toward the LCD 104. The light extractor surface 120 directs the light toward the LCD 104.
The light then first strikes the reflective polarizer 106, which allows only light with the correct polarization angle to pass. The light that passes through the reflective polarizer 106 backlights the LCD 104 to provide an image. The polarizer angle of the reflective polarizer 106 may be aligned to the polarizer angle on the back of the LCD 104.
Light which strikes the reflective polarizer 106 that is not of the correct polarization angle is reflected back by the reflective polarizer 106 and strikes the front side of the diffuser 108, which is the diffuse surface side. The diffuse surface of the diffuser 108 scrambles the polarization of the light and reflects a significant portion of the light back towards the reflective polarizer 108. The light portion of the reflected light
- 9 with the correct polarization is passed through the reflective polarizer 106 and backlights the LCD 104.
Light continues to be reflected in the light pipe until the light is absorbed or exits from the top of the light pipe 110. The diffuser 108 may be a one-sided diffuser having depolarization backscattering properties in conjunction with a reflective polarizer. The diffuser may comprise polarization scrambling reflective back diffuser materials.
While the diffuser 108 slightly reduces the brightness of the LCD 104 at the outer viewing angles, the diffuser 108 increases the luminance of the light in the central angles more than 20%. The increase is the result of a majority of the light does not reenter the light cavity where the absorption losses are greater. In addition the use of a diffuser 108 greatly reduces the edge effects of the light pipe 110 comparable to the CCFL-based devices.
Various diffuser materials may be used on each of the two surfaces of the diffuser 108 to optimize the luminance gain. Other brightness enhancement films (BEF) may also be used to optimize the luminance gain.
The LCD 104 may comprise an active matrix liquid crystal display (AMLCD) or another type of LCD. The frames 102 and 114 may be a metal frame or other type of frame. The frame member 114 may be a metal frame that conducts heat from the circuit board 116. The reflective polarizer 106 may be a dual brightness enhancement film - diffuse (DBEF-D) reflective polarizer. The DBEF-D reflective polarizer 106 allows only light that is properly polarized/orientated to pass to the AMLCD 104. The EDR 118 comprises a polarization scrambling film that
scrambles the polarization of the light and reflects the light toward the diffuser 108. The circuit board 116 may have stiffeners 122 on the center portion and on the folded tabs as illustrated in Figure 1 by the thicker regions of the circuit board 116. Stiffeners 122 may be located on the opposite side of the circuit board 116 from the LEDs 126, on the opposite side of the circuit board 116 from the LED control circuits 128, and in the center portion of the circuit board 116 opposite the exposed ground plane.
The circuit board 116 may include two folds in each tab as illustrated in Figure 3. The LED control circuits 128 may be on a first folded region of the tabs and the LEDs 126 may be on the second folded region of the tabs. The folds of the tabs of the circuit board 116 may form substantially 45 degree angles, such that the LEDs 126 are perpendicular to the center region of the circuit board 116. The LEDs 126 and the LED control circuits 128 may be located on the same side of the circuit board 116.
The circuit board 116 may also provide a heat sinking capability and interconnection. The center portion of the circuit board 116 may include an exposed ground plane that is in contact with the frame member 114 for transferring heat generated by the LEDs to the frame member 114. An optional thermal conductive material may be disposed between the circuit board 116 and the frame member 114 to improve the thermal conductivity. The thermal conductive material is especially important when an air gap exists between the circuit board 116 and the frame member 114. The thermal conductive material may be a pressure sensitive adhesive (PSA) material such as Bond
- 11 Ply, which is available from The Bergquist Company in Chanhassen, Minnesota.
In one aspect, the circuit board 116 is a flexible circuit board having elastomeric properties, which allow the board to be deformed without damage to the components and the connections between the components. In another embodiment, the circuit board 116 is a flexible circuit board that may be capable of small bend radiuses less than 1 mm and may be extremely thin, such as 2 mils thick with 35p of copper on both sides totaling approximately 3.8 mile. The base insulator may be Kapton-based substance, such as Polyimide, that is extremely resilient to environmental and mechanical stresses. Eight mil space and trace is available for the less expensive HD material. The circuit board 116 may also assist in thermal heat sinking. The cathodes ends of the LEDs 126 may be soldered to a ground plane on the circuit board 116 that is connected with a frame member 114 to heat sink heat from the LEDs. The heat flow path may dissipate toward the rear of the LCD display 100. The LCD 104 may be a 3.8" AMLCD.
In one aspect, the phosphorized material 130 and the light pipe 110 are combined to form a phosphor coated or impregnated light pipe for use with the non-white LEDs.
In another aspect, the phosphor material may be placed between the light pipe 110 and the reflective polarizer 106. Various means exist to couple the light from LEDs into a light pipe, such as using total internal reflection with the diodes facing up or tensing the edge of the light pipe. Other techniques of reflective
- 12 polarizers may be used including a wire grid reflective polarizer. An LCD device may have the LEDs placed behind the AMLCD, thus eliminating the need for a light pipe.
In this case, the phosphor material would be placed somewhere in the optical path between the LEDs and the reflective polarizer.
The phosphorized material 130 may be a phosphorized silicone rubber, such as part number KLY5-8D3 from Asahi Rubber Inc. (ARI International Corporation) of Arlington Heights, Illinois. The LEDs 126 may be any type or make of LEDs including Infineon Technology AG. part number LB AG73-N24. The Infineon LED has a luminance rating of 35-
45 mad which corresponds to 105-135 mlm per LED. Other LEDs, including more powerful LEDs, may be used.
The relative spectral radiance from blue LEDs and Asahi Rubber's phosphorized rubber, a reflective polarizer with diffuser configuration, and an EDR results in an estimated 245 Nits for an LCD device with SO LBDs of the more powerful Q1 luminance level parts with a rating of 2X (71-90 mod) and 30mA POWER TOPLED0. The blue LEDs at 245 Nits may have about 25% less luminance than with white LEDs that have 332 Nits. The may be due in part to a non-optimal phosphor conversion. Once optimized, the converted blue light may become more greenish similar to the light produced by conventional white LEDs. Another advantage of using the phosphorized material is that the white color coordinates of the converted light can be controlled.
- 13 Figure 3 represents a top view of a flexible circuit board layout 300 for a LED circuit. The flexible circuit board-based device 300 includes a flexible circuit board 302 and various devices, including the parallel LED circuit 400 (Figure 4) or a series LED drive circuit or other circuits, may be mounted on the flexible circuit board 302. While the flexible circuit board 302 is shown in a completely flat position, when in use, the flexible circuit board 302 may have the tabs 350, 352, and 354 folded along the dashed lines 308 and 310. The folds may be at substantially 45 degrees such that the LEDs 304 face inwardly and are substantially perpendicular to the center region of the flexible circuit board 302 A folded flexible circuit board 302 may be configured as the circuit board 116 illustrated in the cross-section of Figure 2. Other configurations may also be used including a single fold configuration.
While Figure 3 illustrates 12 to 14 LEDs per tab region, other number of LEDs may be used, for example, 2 to 200 LEDs per tab region. The number of LEDs per each tab may be, but need not be, the same. Different types of LEDs may be used on a flexible circuit board 302. Likewise, while Figure 3 illustrates a two to one ratio of LED control circuits 306 to LEDs 304, the number of LED control circuits 306 may vary depending on the application. The flexible circuit board 302 may be any flexible circuit board material, such as Standard Flex, Novaflex HD, and Novaflex VHD, available from Sheldahl Inc. of Northfield, Minnesota.
The LEDs 304 may be located around the perimeter of the flexible circuit board 302. The folding of the flexible circuit board 302 enables the LEDs 304 and the LED control circuits 306 and other related circuits, for such as circuit 322, to be located on one single of the flexible circuit board 302. The circuit 322 may correspond to circuits 40G, 408 and 410 of Figure 4.
The temperature sensor 340, may correspond to the thermal resistor RT1 of Figure 4. Such a single sided component placement is desirable for cost and manufacturability reasons. Additionally, when the components are located on the top side of the flexible circuit board 302 stiffeners, such as the stiffener 122 illustrated in Figure 2, may be used across portions of the bottom side of the flexible circuit board 302. The stiffener may be a polyester-based stiffener material.
The flexible circuit board 302 may be used to directly substituted CCFL circuits with little or no mechanical modifications. The flexible circuit board 302 eliminates the rear metal shield, provides a location for the LED control circuit 306, and may use a flexible interconnect for power and PWM control.
The top surface of the flexible circuit board 302 may include an exposed ground plane. The ground plane may include a majority of the central region of the flexible circuit board 302 and regions in the tabs 350, 352 and 354 that are not used for routing power and signals between the LEDs 304, the LED control circuits 306, and the other circuits 322. The bottom side of the flexible
circuit board 302 may include an exposed voltage plane and signal routing lines.
In one aspect, the flexible circuit board 302 may include ground tabs 330 and 332. The ground tabs 330 and 332 may be flexible tabs that can be inserted into an existing LCD frame to connect the ground plane of the flexible circuit board 302 to the frame. The ground plane on the top of the flexible circuit board 302 may be connected directly with a frame to provide LED heat sinking by connecting the cathodes of the LEDs to a heat sinking device, such as a metal frame. Such heat sinking results in a passive LED cooling method that is more cost effective than the other methods such as thermal electric coolers or spring clips. While the flexible circuit board 302 costs more than traditional rigid circuit boards, directly mounting the LEDs 304 and the LED control circuits 306 to the flexible circuit board 302 eliminates the need for daughter boards or other interconnecting devices or the more expensive side-
lighting LEDs.
Also, the flexible circuit board 302 may include various cutouts, such as cutout 324, so that the flexible circuit board 302 may directly replace a CCFL device.
Additionally, mounting tabs 320 and 321 and other devices may be integrated into the flexible circuit board 302 to allow the flexible circuit board 302 to directly replace a CCFL device or other device.
Figure 4 represents a circuit diagram of a parallel LED circuit 400 according to an embodiment. The LED circuit
- 400 may include a parallel LED array 402, a current source circuit 404, a control circuit 406, an optional temperature aerating circuit 408, and an optional temperature monitoring circuit 410. While the LED circuit 400 is described with reference to a parallel LED drive circuit, other LED drive circuits may also be used including a series drive circuit and a hybrid drive circuit. The parallel LED array 402 includes a plurality of LEDs D2, D3, and Dn connected in parallel. The LEDs may be white or colored LEDs, such as red, green, and blue LEDs, other colored LEDs, ultraviolet (W) LEDs, or a combination of different types of LEDs. The LED labeled "Dn" represents the nth LED where n is the total number of diodes. While Figure 4 illustrates only three LEDs in the LED array 402, the LED array 402 may have any number of LEDs, for example 2 to 1,Ooo LEDs for some applications and many more LEDs, such as 50,000, for other applications. There essentially is no limit to the number of LEDs that could be in the LED array 402. Any additional LEDs will have corresponding current source transistors and emitter resistors in a similar configuration as the current source transistors Q3, Q4, and Qn and the emitter resistors R7, R8, and Rn.
The LEDs D2, D3, and Dn may each be separately current sourced to provide consistent LED brightness. This eliminates most brightness variations caused by LED forward voltage variations. The cathode terminals of each of the LEDs D2, D3, and Dn are connected with ground at a ground node. The common ground connection may be
- 17 connected with a heat sink to transfer heat away from the LEDs. The anode terminal of the LEDs D2, D3, Dn connects with the current source transistor Q3, Q4, Qn. By connecting the cathode terminal of the parallel LEDs D2, D3, and Dn diodes to ground, a superior thermal conductive path is established that reduces the LED junction temperature and equalizes the junction temperatures among the parallel diodes. Since the luminous intensity of an LED decreases dramatically as the junction temperature increases, equalization of the junction temperatures helps maintain a more uniform brightness among the LEDs D2, D3, and Dn.
The current source circuit 404 supplies the LED array 402 with substantially uniform current to each LED, D2, D3, and Dn. Since the brightness of an LED is directly related to the current passing through the LED, accurate control of the LED current allows proper LED performance and life expectancy. The anode terminals of the LEDS D2, D3, and Dn are connected with a collector terminal of the respective current source transistor, Q3, Q4, and Qn. A common control node interconnects the base terminals of the current source transistors Q3, Q4, and Qn. The emitter terminals of the current source transistors, Q3, Q4, and Qn, are connected to the supply voltage via an emitter resistor R7, R8, and Rn, respectively. The current source transistors, Q3, Q4, and Qn may have substantially identical characteristics. Thus, the characteristic of the current source transistors, Q3, Q4, and Qn with respect to various collector currents (Ic) and base to emitter voltages (Vbe) will be substantially similar since the transistor temperatures will be
- 18 substantially identical. The base terminals of the current source transistors, Q3, Q4, and Qn are connected at a common control node 454.
The emitter resistors R7, R8, and Rn further reduce variations in the current from the current source transistors, Q3, Q4, and On. Thus, the parallel LEDs D2, D3, and Dn maintain consistent brightness. The emitter resistor R7, R8, and Rn preferably may have substantially identical characteristics. When the LEDs, D2, D3, and Dn, are white LEDs, the emitter resistors R7, R8, and Rn may be 0.1 to 1,000 Ohm resistors. The emitter resistors R7, R8, and Rn preferably have low resistance, such as 5 Ohms. When color diodes are being driven by the current source circuit 404, the value of the emitter resistors R7, R8, and Rn may be selected to achieve a different desired current level for each LED to achieve proper white balance.
The control circuit 406 provides fault tolerance protection when one or more LEDs in the LED array 402 fails. An LED may fail by a short or an open. When an LED fails open, the LED disconnects the collector terminal of the current source transistor. When an LED fails closed, the LED connects the collector terminal of the current source transistor to ground. Such LED failures tend to affect the voltage at the common control node 454 of the current source transistors. The control circuit 406 stabilizes the voltage at the common base node via feedback circuitry. When the voltage at the common base node is stable, the remaining LEDs continue to be driven at the prescribed level.
- 19 The transistor Q2 and the zener diode D1 provide load dumping when an LED fails open. The current that would have passed through the LED isdiverted to the base terminal of the current source transistor connected with the LED that is open. This additional current is received by the transistor Q2 and dissipated through the zener diode D1. The number of LEDs that may fail in the open position while the LED circuit 400 remains operational is limited by the power rating of the transistor Q2 and the zener diode D1. For example, a zener diode D1 with a aerated power limit of 500 mW allows for four open LEDs. A resistor or other device may alternatively by used in place of the zener diode D1.
An LED failure by a short is an unlikely failure.
However, if an LED shorts out, the current source transistor associated with that LED continues to supply the shorted LED with the same current as the other LEDs.
Thus, the brightness of the other LED is unaffected by the shorted LED.
A sample current source circuit 412 includes a transistor-
Q1 and a resistor R2 that have characteristics that are substantially similar to those of the current control transistors Q3, Q4, and On and the emitter resistors R7, R8, and Rn. By mirroring the characteristics of the current source circuit, the current through the sample current source circuit 412 may be monitored to estimate the current that passes through the LEDs. The sample current source circuit 412 provides a current substantially similar to the current that passes through
- 20 each of the LEDs, D2, D3, Dn. The sample current is converted by a resistor R3 to a reference voltage. The sample current source circuit 412 eliminates the need for additional circuitry to sample the actual current through the LEDs, D2, D3, Dn. The sample current source circuit 412 allows the cathodes of the LEDs, D2, D3, Dn to be connected with the ground node instead of sampling circuitry The resistor R1 provides an offset to ensure that the LEDs can be completely turned off even with a small output voltage at node 450 commonly associated with PWM controllers.
The control circuit 406 uses a current feedback circuit to more precisely control the current to the parallel LEDs. The additional control allows the parallel LEDs to be operated closer to their maximum rating, which is where the LEDs are at their brightest. The error amplifier U1 of the control circuit 406, may be configured to provide a bandwidth limiting function that eliminates high rate of change currents transients. This elimination reduces or completely suppresses electro-
magnetic interference (EMI) emissions.
The error amplifier U1, an operational amplifier, typically operates in a linear mode of operation. The input to the error amplifier U1 receives a voltage divided output from the operational amplifier U2. The output voltage from operational amplifier U2 is divided by the voltage divider formed by the resistors R4 and R5.
The temperature aerating circuit 408 aerates current to the LED array 402 as the temperature increases to prolong the life expectancy of the LEDs. The temperature
- 21 derating circuit 408 is connected with the control circuit 406 and an intensity input node 450. The input voltage from the operational amplifier U2 controls the brightness of the LED array 402. The operational amplifier U2 is configured as a differential amplifier where the ratios of the operational amplifiers resistors are substantially balanced, that is R12/R11 = R10/R9.
When the ratios of the operational amplifier's resistor R12/R11 and R10/R9 are both substantially equal to one, the differential gain of the operational amplifier U2 is substantially unity. When the output of the operational amplifier U4 is at substantially ground during a non-
derating condition, the operational amplifier U2 passes the input signal from input node 450 with the gain set by the resistor ratios, which may be a unity gain. The intensity level signal may be a steady DC voltage, a pulse width modulated signal, or an other type of signal.
The aerating operational amplifier U4 normally operates in a rail-to-rail mode. When the LED array 402 is operating in a normal operating temperature range, the output of the aerating operational amplifier U4, known as the temperature aerating level, is substantially ground.
As the temperature of the LED array 402 increases, the temperature aerating level increases after a predetermined LED threshold temperature is reached.
Since the thermal resistor RT1 is connected with the same ground and preferably in close proximity to the LED array 402, the resistance of the thermal resistor RT1 varies as a function of the temperature of the solder near the cathode terminals of the LEDs D2, D3, and Dn. The thermal resistor RT1, also called a temperature sensor,
- 22 has a rest-stance that varies as a function of a measured temperature. For example, the thermal resistor RT1 may be a model KT230 available from Infineon Technologies A.G. 1730 N. First Street, San Jose, Ca 95112. The model KT230 is a temperature dependent resistor with a resistance tolerances of +/-3\ at 1,000 Ohms, a temperature range of -50 degree Centigrade to +150 degree Centigrade, and is available in SAD or leaded or customized packages. The model KT230 has a linear output, a positive temperature coefficient, a long term stability, a fast response time, and is polarity independent due to symmetrical construction. Other commonly available temperature sensors, such as models LM135 and LM50 from the National Semiconductor, Inc., may also be used.
The operational amplifier U2 receives a higher output voltage from the aerating operational amplifier U4 through resistor R11. The output voltage from the aerating operational amplifier U4 acts as a negative offset to the input voltage at the input node 450. By reducing the output voltage of the operational amplifier U2, the error amplifier U1 increases its output voltage which causes the voltage at the common base node 454 to be increased. This results in the current source transistors Q3, Q-4, and On allowing less current to flow through the LED array 402. The LEDs D2, D3, and On then become less bright as the temperature increases. For example, if the input voltage at the input node 450 is 5 VDC and the temperature aerating level is 1.5 V, the output of the operation amplifier U2 is 3.5V. The temperature aerating circuit 408 may shut off the LED
array 402 if the measured temperature reaches a predetermined temperature threshold.
The temperature monitoring circuit 410 provides a temperature output signal at output node 452 that indicates a temperature associated with the LED array 402. The LED temperature output signal may be a function of the LED temperature as measured by the thermal resistor RT1. The thermal resistor RT1 may be used for the temperature monitoring circuit 410 and the temperature aerating circuit 408. The temperature monitor amplifier U3 monitors a voltage difference between a first voltage divider circuit Rl9 and R20 and a second voltage divider circuit R17 and RT1 to provide an output voltage that is proportional to the LED temperature. The output of the temperature monitor amplifier U3 is connected with the output node 452. The temperature monitoring output 452 may be used by an external controller to adjust the drive level to input 450 to compensate for LED luminance changes as a function of temperature.
The input node 450 of the LED circuit 400 may receive an input signal from a microprocessor or other controller.
The input signal may be a pulse width modulated ("PWM,') signal, a DC voltage signal, or other type of signal. A PAM input signal controls the intensity of the LED based on the duty cycle and/or the voltage level of the input signal. Generally, as the duty cycle of the input signal increases, the LEDs D2, D3, and Dn become brighter. A DC voltage input signal controls the intensity of the LED based the voltage level of the input signal. Generally,
- 24 as the voltage level at the input node 450 increases, the LEDs D2, D3, and Dn become brighter.
The LED circuit 400 may operate with a supply voltage of between 1 volt to 15 volts, and preferably it operates at approximately 5 volts. Since the LED circuit 400 includes a parallel LED array 402, a high power inverter and higher supply voltage commonly required for serial LED circuits is not required. The LED circuit 400 may be a band limited low electromagnetic interference circuit controlled by the values of R4, R5, C3, R3, and C2.
The LED circuit 400 of Figure 4 may include components as indicated in Table 1. Other types of components and components of different values may also be used in the LED circuit 400.
TABLE 1
Ref. Description
C1 A capacitor, for example a 1 pF capacitor.
C2-3 A capacitor, for example a 0.01 OF capacitor.
._ _ Q1-4 A PUP transistor, for example, a model MBT3906DWlT1 transistor from Motorola, Inc. that is available in a dual package.
Qn A PNP transistor, for example, a model MBT3906DWlT1 transistor from Motorola, Inc. that is available in a dual package.
D1 A Zener diode, for example a 3.3 volt Zener diode.
D2-3 A light emitting diode. For example, white SIDELED
- 25 TABLE 1
Ref. Description
Infineon model LWA67C, a white LED from Infineon model LW E673 or LW E67C, red LED model LSA677-Q, green LED model LTA673-R24, or a blue LED LBA673 N24 all from Infineon Technology AG.
Dn A light emitting diode. For example, white SIDELED Infineon model LWA67C, a white LED from Infineon model LW E673 or LW E67C, red LED model LSA677-Q, green LED model LTA673-R24, or a blue LED LBA673-
N24 all from Infineon Technology AG.
U1-4 An operational amplifier, for example a model LMV321 available from National Semiconductor Corp. or a model TLC 2274 Rail-to-Rail Operational Amplifier available from Texas Instruments, Inc. R1 A resistor, for example a 4.99K Ohms resistor.
Other resistance values may also be used, for example, 0 5K to 50K Ohms.
R2 A resistor, for example a 5 Ohms resistor. Other resistance values may also be used, for example, 0.5 to 500 Ohms.
R3 A resistor, for example a 100 Ohms resistor. Other resistance values may also be used, for example, 0.1 to 10K Ohms.
R4 A resistor, for example a 16.5k Ohms resistor.
Other resistance values may also be used, for example, 165 to 1650K Ohms.
R5 A resistor, for example a 25K Ohms resistor. Other resistance values may also be used, for example,
- 26 TABLE 1
Ref. Description
250 to 2,500K Ohms.
R6 A resistor, for example a 4.99K Ohms resistor.
Other resistance values may also be used, for example, 0.5K to 50K Ohms.
R7 A resistor, for example a 5 Ohms resistor. Other resistance values may also be used, for example, 0.5 to 500 Ohms.
R8 A resistor, for example a 5 Ohms resistor. Other resistance values may also be used, for example, 0.5 to 500 Ohms.
Rn A resistor, for example a 5 Ohms resistor. Other resistance values may also be used, for example, 0.5 to 500 Ohms.
R9-21 A resistor, for example a 20K Ohms resistor. Other resistance values may also be used, for example, 200 to 200K Ohms.
RT1 A resistor with a temperature dependent resistance, for example KT230 available from Infineon Technology A.G.
Figure 5 represents an embodiment of an LCD device 500 that includes white LEDs. The LCD device S00 has corresponding element numbers and a similar operation to the LCD device 100 shown in Figures 1 and 2. However, the LCD device 500 uses white LEDs rather than the non white LEDs shown in LCD device 100. The LCD device 500 also does not need the phosphorized material used in the LCD device 100. However, LCD device 500 may use a
- 27 phosphorized material to improve the light properties from a white LED.
The LCD device 500 includes a frame 502 and 514, a liquid crystal display (LCD) 504, a reflective polarizer 506, a diffuser 508, a light pipe 510, an enhanced specular reflector (ESR) 524, a printed circuit board 512, side LED arrays 526, an LED controller circuit 528, a circuit board 516, an enhanced diffuser reflector (EDR) 518, a light extracting surface 520, and a thermally conductive material 534. The LCD 504 may be an active matrix liquid crystal display (AMLCD). The side LED arrays 526 comprise white LEDs as previously discussed. The LED arrays 526 and the ESR 512 have a side reflective configuration as discussed below. In an aspect, the LCD device 500 with white LED's has about one-third the LEDS as a comparable LCD device using non-white LEDs. In another aspect, the white LEDs have about 2.5 times the brightness of the non-white LEDs. The ESR 524 and the thermally conductive material 534 are discussed below.
Figure 6 represents another embodiment of an LCD device 600 that includes white LEDs. The LCD device 600 has corresponding element numbers and a similar operation to the LCD device 500 shown in Figure 5. The LCD device 600 includes a frame 602 and 614, an LCD or an AMLCD 604, a reflective polarizer 606, a diffuser 608, a light pipe 610, an enhanced specular reflector (ESR) 624, a printed circuit board 612, an LED array 626, an LED controller circuit 628, a circuit board 616, an enhanced diffuser reflector (EDR) 618, a thermally conductive material 634, and a light extracting surface 620. The circuit board
616 may be thinner than the printed circuit board 612.
The circuit board 616 is thermally connected with the frame 602 via the thermally conductive material 634. The LED 626 and the ESR 624 have a top reflective configuration. The ESR 624 may be angled at about 45 degrees to reflect the light from the LED 626 such that a side LED is not required. The frame 602 also may form a light cavity that contains the light pipe 610, the ESR 612, the LED array 626, and the diffuser 608. The light cavity may include the circuit board 616.
Figure 7 represents another embodiment of an LCD device 700 that includes non-white LEDs. The LCD device 700 has corresponding element numbers and a similar operation to the LCD device 100 shown in Figures 1 and 2. The LCD device 700 includes a frame 702 and 714, an LCD or an AMLCD 704, a reflective polarizer 706, a diffuser 708, a light pipe 710, an enhanced specular reflector (ESR) 724, a printed circuit board 712, LEDs 726, an LED controller circuit 728, a circuit board 716, an enhanced diffuser reflector (EDR) 718, a light extracting surface 720, and a thermally conductive material 734. The LEDs comprise non-white LEDs as previously discussed.
The ESR 724 is configured at the ends of the light pipe 710. The ESR 724 reflects light from the LEDs 726 into the light pipe 710. In one aspect, each LED 726 has a top reflective configuration in relation to the light pipe 710 and the ESR 724. The LEDs 726 are positioned so the top or light emitting surfaces of the LEDs 726 are essentially perpendicular to the ends of the light pipe 770. In one aspect, ESR 724 has a planar surface forming
- 29 an angle of about 45 degrees with the top surface of the LED and forming an angle of about 45 degrees with the end of the light pipe. Light from the LEDs is top reflected by the ESR 724 into the light pipe 710.
The thermally conductive material 734 is disposed between the frame 714 and the circuit board 716. In one aspect, the thermally conductive material is a thermally conductive pressure sensitive adhesive such as the Bergquist Bond Ply 100 available from the Bergquist Company in Chanhassen, Minnesota. Other thermally conductive adhesives and materials may be used.
Figure 8 represents a further embodiment of an LCD device 800 that includes non-white LEDs. The LCD device 800 has corresponding element numbers and a similar operation to the LCD device 700 shown in Figure 7. The LCD device 800 includes a frame 802 and 814, an LCD or an AMLCD 804, a reflective polarizer 806, a diffuser 808, a light pipe 810, an enhanced specular reflector (ESR) 824, a printed circuit board 812, a side LED array 826, and LED controller circuit 828, a circuit board 816, a thermally conductive material 834, an enhanced diffuser reflector (EDR) 818, and a light extracting surface 820. The circuit board 816 may be thinner than the printed circuit board 812. The circuit board 816 is thermally connected with the frame 802 via the thermally conductive material 834. The LED 826 and the ESR 824 have a side reflective configuration. The LCD devices may have other configurations and arrangements including those with fewer and additional
- 30 parts. The edge lighting configurations, including the side and top reflective versions shown in the embodiments, can provide color diffuser and luminescence uniformity advantages. The light pipe also may have a square, rectangular, or other shape to reduce or eliminate the direct observation of the LEDs by a user.
Various embodiments of the invention have been described and illustrated. However, the description and
illustrations are by way of example only. Other embodiments and implementations are possible within the scope of this invention and will be apparent to those of ordinary skill in the art. Therefore, the invention is not limited to the specific details, representative embodiments, and illustrated examples in this description. Accordingly, the invention is not to be
restricted except in light as necessitated by the accompanying claims and their equivalents.
Claims (52)
1. A liquid crystal display (LCD) backlighting device, comprising: a nonwhite light emitting diode; a liquid crystal display; and a phosphorized material located between the light emitting diode and the liquid crystal display, where the phosphorized material down converts light from the light emitting diode toward white light spectral radiance.
2. An LCD backlighting device according to claim 1, wherein the non-white light emitting diode comprises a light emitting diode is selected from the group consisting of blue light emitting diodes and ultraviolet light emitting diodes.
3. An LCD backlighting device according to claim 1 or claim 2, further comprising a second non-white light emitting diode that differs in color with the non-white light emitting diode comprises a plurality of different colored light emitting diodes.
4. An LCD backlighting device according to any one of claims 1 to 3, wherein the non-white light emitting diode is located along a perimeter of a flexible circuit board.
5. An LCD backlighting device according to any one of claims l to 4, wherein the non-white light emitting
- 32 diode has a top reflective orientation with the light pipe.
6. An LCD backlighting device according to any one of claims 1 to 4, wherein the non-white light emitting diode has a side reflective orientation with the light pipe.
7. An LCD backlighting device according to any one of claims 1 to 6, further comprising a polarization scrambling material between the non-white light emitting diode and the light pipe, where the polarization scrambling material comprises apertures located adjacent to the non-white light emitting diode.
8. An LCD backlighting device according to any one of claims 1 to 7, further comprising: a light pipe; and a reflective polarizer; wherein light from the light pipe passes through the reflective polarizer before backlighting the liquid crystal display.
9. An LCD backlighting device according to any one of claims 1 to 8, wherein the phosphorized material comprises a phosphorized rubber.
10. An LCD backlighting device according to claim 9, wherein the phosphorized material comprises a phosphorized silicone material.
11. An LCD backlighting device according to any one of claims 1 to 10 further comprising an enhanced specular reflector disposed near the nonwhite light emitting diode and the light pipe, wherein light from the non-
white light emitting diode reflects from the enhanced specular reflector into the light pipe.
12. An LCD backlighting device according to any one of claims 1 to 11, further comprising a polarization scrambling material between the nonwhite light emitting diode and the light pipe, where the polarization scrambling material comprises apertures located adjacent to the non-white light emitting diode.
13. An LCD backlighting device according to claim 12, further comprising a second polarization scrambling material located along the light pipe opposite the liquid crystal display.
14. An LCD backlighting device according to any one of claims 1 to 13 further comprising an enhanced diffuser reflector near the light pipe.
15. An LCD backlighting device according to any one of claims 1 to 14, further comprising a diffuser between the light pipe and the reflective polarizer.
16. An LCD backlighting device according to claim 15, wherein the diffuser comprises a one-sided diffuser.
3 _
17. An LCD backlighting device according to claim 15 or claim 16, further comprising a polarization scrambling material near the diffuser.
18. A liquid crystal display (LCD) device, comprising: a non-white light emitting diode; a light pipe; a spectrum converting material between the non white light emitting diode and the light pipe; a light extracting surface located near a first side of the light pipe; a diffuser located near a second side of the light pipe, where the first and second sides are opposite sides of the light pipe; a reflective polarizer; and a liquid crystal display; wherein light from the non-white light emitting diode and converted by the spectrum converting material enters the light pipe passes through the diffuser, the reflective polarizer, then backlights the liquid crystal display.
19. An LCD display device according to claim 20, wherein the spectrum converting material comprises a phosphorized material.
20. An LCD display device according to claim 19, wherein the phosphorized material is disposed adjacent to the light extracting surface.
21. An LCD display device according to claim 19, wherein the phosphorized material is disposed between the light pipe and reflective polarizer.
22. An LCD display device according to any of claims 18 to 21, wherein the light emitting diode comprises a top lighting light emitting diode.
23. An LCD display device according to any of claims 18 to 22, wherein the liquid crystal display comprises an active matrix liquid crystal display.
24. An LCD display device according to any of claims 18 to 23, wherein the diffuser comprises a phosphor coating.
25. An LCD display device according to any of claims 18 to 24, wherein the light pipe comprises a phosphor coating.
26. An LCD display device according to any of claims 18 to 25, wherein the light pipe comprises a phosphor impregnated light pipe.
27. An LCD display device according to any of claims 18 to 26, wherein the non-white light emitting diode comprises a blue light emitting diode.
- 35
28. An LCD display device according to any of claims 18 to 27, wherein the non-white light emitting diode comprises an ultraviolet light emitting diode.
29. An LCD display device according to any of claims 18 to 28, wherein the non-white light emitting diode is disposed near an edge of the light pipe.
30. An LCD display device according to any of claims 18 to 28, wherein the non-white light emitting diode is located along a perimeter of a circuit board.
31. An LCD display device according to any of claims 18 to 30, wherein the circuit board comprises a flexible circuit board.
32. An LCD display device according to any of claims 18 to 31, wherein the non-white light emitting diode has a top reflective orientation with an enhanced specular reflector near the end of the light pipe.
33. An LCD display device according to any of claims 18 to 31, wherein the non-white light emitting diode has a side reflective orientation with an enhanced reflector near the end of the light pipe.
34. An LCD display device according to any of claims 18 to 33, further comprising a thermally conductive material between the circuit board and a frame.
À 37
35. An LCD display device according to any of claims 18 to 34, further comprising an enhanced diffuser reflector near the light pipe.
36. The LCD device of claim 20, further comprising: a second non-white light emitting diode that differs in color than the non-white emitting diode, where the spectrum converting material comprises first and second regions, where the first region converts light from the light emitting diode toward a first white light spectral radiance and the second region converts light from the second light emitting diode toward a second white light spectral radiance.
37. A liquid crystal display (LCD) device, comprising: a light emitting diode that emits non-white light; a spectrum converting material; a diffuser; a reflective polarizer; and a liquid crystal display; wherein light from the light emitting diode is converted by the spectrum converting material before the converted light passes through the diffuser, the reflective polarizer, before backlighting the liquid crystal display.
-
38 38. An LCD display device according to claim 37, wherein the liquid crystal display comprises an active matrix liquid crystal display.
39. An LCD display device according to claim 37 or claim 38, further comprising an enhanced diffuser reflector near the light pipe.
40. A liquid crystal display, comprising: a non-white light emitting diode; a light pipe with a phosphor coating that converts the spectrum of the non-white light emitting diodes and the light pipe; a light extracting surface located near a first side of the light pipe; an enhanced diffuser reflector located near an opposite side of the light pipe; a diffuser located near a second side of the light pipe, where the first and second sides are opposite sides of the light pipe; a reflective polarizer; and a liquid crystal display, wherein light from the light pipe passes through the diffuser, the reflective polarizer, then backlights the liquid crystal display.
41. A liquid crystal display (LCD) device, comprising: a white light emitting diode; a light pipe;
- 39 a light extracting surface located near a first side of the light pipe; a diffuser located near a second side of the light pipe, where the first and second sides are opposite sides of the light pipe; a reflective polarizer; and a liquid crystal display; wherein light from the white light emitting diode enters the light pipe and passes through the diffuser, the reflective polarizer, then backlights the liquid crystal display.
42. An LCD device according to claim 41, wherein the white light emitting diode is located along a perimeter of a circuit board.
43. An LCD display device according to claim 41 or claim 42, wherein the circuit board comprises a flexible circuit board.
44. An LCD display device according to any of claims 41 to 43, further comprising a thermally conductive material between the circuit board and a frame.
45. An LCD display device according to any of claims 41 to 44, wherein the white light emitting diode has a top reflective orientation with the light pipe.
- 40
46. An LCD display device according to any of claims 41 to 44, wherein the white light emitting diode has a side reflective orientation with the light pipe.
47. An LCD display device according to any of claims 41 to 46, wherein the diffuser comprises a one-
sided diffuser.
48. An LCD display device according to any of claims 41 to 47, further comprising a polarization scrambling material between the white light emitting diode and the light pipe.
49. An LCD display device according to claim 48, wherein the polarization scrambling material forms apertures near the white light emitting diode.
50. An LCD display device according to claim 48 or claim 49, further comprising a second polarization scrambling material located along the light pipe opposite the liquid crystal display.
51. An LCD display device according to any of claims 41 to 50, further comprising an enhanced diffuser reflector near the light pipe.
52. An LCD display device according to any of claims 41 to 51, further comprising an enhanced specular reflector disposed near the white light emitting diode and the light pipe, where light form the white light
- 41 emitting diode reflects from the enhanced specular reflector into the light pipe.
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US26176001P | 2001-01-16 | 2001-01-16 | |
US10/040,864 US6930737B2 (en) | 2001-01-16 | 2001-12-28 | LED backlighting system |
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Publication Number | Publication Date |
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GB0200653D0 GB0200653D0 (en) | 2002-02-27 |
GB2374714A true GB2374714A (en) | 2002-10-23 |
GB2374714B GB2374714B (en) | 2003-04-09 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB0200653A Expired - Fee Related GB2374714B (en) | 2001-01-16 | 2002-01-14 | LED backlighting system |
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US (2) | US6930737B2 (en) |
DE (1) | DE10201052B8 (en) |
GB (1) | GB2374714B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1533851A2 (en) * | 2003-11-20 | 2005-05-25 | Sumitomo Electric Industries, Ltd. | Light-emitting diode and semiconductor light-emitting device |
GB2428859A (en) * | 2005-08-01 | 2007-02-07 | Avago Technologies General Ip | Light source and apparatus including a light source |
Families Citing this family (257)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5910854A (en) | 1993-02-26 | 1999-06-08 | Donnelly Corporation | Electrochromic polymeric solid films, manufacturing electrochromic devices using such solid films, and processes for making such solid films and devices |
US5668663A (en) | 1994-05-05 | 1997-09-16 | Donnelly Corporation | Electrochromic mirrors and devices |
US6891563B2 (en) | 1996-05-22 | 2005-05-10 | Donnelly Corporation | Vehicular vision system |
US6124886A (en) | 1997-08-25 | 2000-09-26 | Donnelly Corporation | Modular rearview mirror assembly |
US6172613B1 (en) | 1998-02-18 | 2001-01-09 | Donnelly Corporation | Rearview mirror assembly incorporating vehicle information display |
US6326613B1 (en) | 1998-01-07 | 2001-12-04 | Donnelly Corporation | Vehicle interior mirror assembly adapted for containing a rain sensor |
US8294975B2 (en) | 1997-08-25 | 2012-10-23 | Donnelly Corporation | Automotive rearview mirror assembly |
US6445287B1 (en) | 2000-02-28 | 2002-09-03 | Donnelly Corporation | Tire inflation assistance monitoring system |
US8288711B2 (en) | 1998-01-07 | 2012-10-16 | Donnelly Corporation | Interior rearview mirror system with forwardly-viewing camera and a control |
US6693517B2 (en) | 2000-04-21 | 2004-02-17 | Donnelly Corporation | Vehicle mirror assembly communicating wirelessly with vehicle accessories and occupants |
US6477464B2 (en) | 2000-03-09 | 2002-11-05 | Donnelly Corporation | Complete mirror-based global-positioning system (GPS) navigation solution |
US6329925B1 (en) | 1999-11-24 | 2001-12-11 | Donnelly Corporation | Rearview mirror assembly with added feature modular display |
US7370983B2 (en) | 2000-03-02 | 2008-05-13 | Donnelly Corporation | Interior mirror assembly with display |
US7167796B2 (en) | 2000-03-09 | 2007-01-23 | Donnelly Corporation | Vehicle navigation system for use with a telematics system |
US7004593B2 (en) | 2002-06-06 | 2006-02-28 | Donnelly Corporation | Interior rearview mirror system with compass |
AU2001243285A1 (en) | 2000-03-02 | 2001-09-12 | Donnelly Corporation | Video mirror systems incorporating an accessory module |
US7581859B2 (en) | 2005-09-14 | 2009-09-01 | Donnelly Corp. | Display device for exterior rearview mirror |
EP1363810B1 (en) | 2001-01-23 | 2007-05-30 | Donnelly Corporation | Improved vehicular lighting system |
US7255451B2 (en) | 2002-09-20 | 2007-08-14 | Donnelly Corporation | Electro-optic mirror cell |
US6590561B1 (en) | 2001-05-26 | 2003-07-08 | Garmin Ltd. | Computer program, method, and device for controlling the brightness of a display |
US6943771B2 (en) | 2001-05-26 | 2005-09-13 | Garmin Ltd. | Computer program, method, and device for controlling the brightness of a display |
EP1313353A1 (en) * | 2001-11-19 | 2003-05-21 | Nokia Corporation | Method and device for operating a light emitting diode |
AU2002360006A1 (en) * | 2001-12-25 | 2003-07-15 | Matsushita Electric Industrial Co., Ltd. | Illumination unit and liquid crystal display device using the unit |
DE10205796C1 (en) * | 2002-02-13 | 2003-10-30 | Behr Hella Thermocontrol Gmbh | Operating device for automobile heating and/or air-conditioning has display field provided by insert in front plate illuminated using non-visible electromagnetic radiation via wavelength converter |
US6918674B2 (en) | 2002-05-03 | 2005-07-19 | Donnelly Corporation | Vehicle rearview mirror system |
US6841947B2 (en) * | 2002-05-14 | 2005-01-11 | Garmin At, Inc. | Systems and methods for controlling brightness of an avionics display |
US7329013B2 (en) | 2002-06-06 | 2008-02-12 | Donnelly Corporation | Interior rearview mirror system with compass |
US7310177B2 (en) | 2002-09-20 | 2007-12-18 | Donnelly Corporation | Electro-optic reflective element assembly |
US7274501B2 (en) | 2002-09-20 | 2007-09-25 | Donnelly Corporation | Mirror reflective element assembly |
KR100628264B1 (en) * | 2002-09-26 | 2006-09-27 | 엘지.필립스 엘시디 주식회사 | back light unit of liquid crystal display device |
DE10260692B4 (en) * | 2002-12-23 | 2009-05-20 | Continental Automotive Gmbh | liquid-crystal display |
US7118438B2 (en) * | 2003-01-27 | 2006-10-10 | 3M Innovative Properties Company | Methods of making phosphor based light sources having an interference reflector |
US7312560B2 (en) | 2003-01-27 | 2007-12-25 | 3M Innovative Properties | Phosphor based light sources having a non-planar long pass reflector and method of making |
US7091653B2 (en) | 2003-01-27 | 2006-08-15 | 3M Innovative Properties Company | Phosphor based light sources having a non-planar long pass reflector |
US20040145289A1 (en) * | 2003-01-27 | 2004-07-29 | 3M Innovative Properties Company | Phosphor based light sources having a non-planar short pass reflector and method of making |
JP2006516828A (en) * | 2003-01-27 | 2006-07-06 | スリーエム イノベイティブ プロパティズ カンパニー | Phosphorescent light source element and manufacturing method |
US7245072B2 (en) * | 2003-01-27 | 2007-07-17 | 3M Innovative Properties Company | Phosphor based light sources having a polymeric long pass reflector |
US20040145312A1 (en) * | 2003-01-27 | 2004-07-29 | 3M Innovative Properties Company | Phosphor based light source having a flexible short pass reflector |
US7091661B2 (en) * | 2003-01-27 | 2006-08-15 | 3M Innovative Properties Company | Phosphor based light sources having a reflective polarizer |
US20040159900A1 (en) * | 2003-01-27 | 2004-08-19 | 3M Innovative Properties Company | Phosphor based light sources having front illumination |
JP3935095B2 (en) * | 2003-03-20 | 2007-06-20 | 株式会社ソフィア | Image display device and light source unit |
KR101148332B1 (en) | 2003-04-30 | 2012-05-25 | 크리, 인코포레이티드 | High powered light emitter packages with compact optics |
US7005679B2 (en) * | 2003-05-01 | 2006-02-28 | Cree, Inc. | Multiple component solid state white light |
ATE408785T1 (en) * | 2003-06-27 | 2008-10-15 | Koninkl Philips Electronics Nv | LIGHT BODY |
DE10345884A1 (en) * | 2003-09-30 | 2005-05-12 | Siemens Ag | Display with backlight unit |
US7446924B2 (en) | 2003-10-02 | 2008-11-04 | Donnelly Corporation | Mirror reflective element assembly including electronic component |
US7308341B2 (en) | 2003-10-14 | 2007-12-11 | Donnelly Corporation | Vehicle communication system |
US7341199B2 (en) * | 2003-11-12 | 2008-03-11 | Siemens Energy & Automation, Inc. | Material handling system with dynamic source tagging |
JP4066953B2 (en) * | 2004-01-13 | 2008-03-26 | セイコーエプソン株式会社 | Electro-optical device and electronic apparatus |
US10499465B2 (en) * | 2004-02-25 | 2019-12-03 | Lynk Labs, Inc. | High frequency multi-voltage and multi-brightness LED lighting devices and systems and methods of using same |
US7408201B2 (en) * | 2004-03-19 | 2008-08-05 | Philips Lumileds Lighting Company, Llc | Polarized semiconductor light emitting device |
US7808011B2 (en) * | 2004-03-19 | 2010-10-05 | Koninklijke Philips Electronics N.V. | Semiconductor light emitting devices including in-plane light emitting layers |
DE102004014788A1 (en) * | 2004-03-24 | 2005-10-27 | Andreas Huck | Illumination for a watch face is provide by a light emitting diode with output into an optical conductor |
JP4590283B2 (en) * | 2004-05-21 | 2010-12-01 | シャープ株式会社 | Backlight unit and liquid crystal display device including the same |
US7255469B2 (en) * | 2004-06-30 | 2007-08-14 | 3M Innovative Properties Company | Phosphor based illumination system having a light guide and an interference reflector |
US7204630B2 (en) * | 2004-06-30 | 2007-04-17 | 3M Innovative Properties Company | Phosphor based illumination system having a plurality of light guides and an interference reflector |
US7182498B2 (en) * | 2004-06-30 | 2007-02-27 | 3M Innovative Properties Company | Phosphor based illumination system having a plurality of light guides and an interference reflector |
US7534633B2 (en) * | 2004-07-02 | 2009-05-19 | Cree, Inc. | LED with substrate modifications for enhanced light extraction and method of making same |
JP2006030783A (en) * | 2004-07-20 | 2006-02-02 | Alps Electric Co Ltd | Liquid crystal display device |
CN101006493B (en) * | 2004-08-16 | 2010-06-09 | 瓦-林·莫 | Virtual keypad input device |
JP4529585B2 (en) * | 2004-08-18 | 2010-08-25 | ソニー株式会社 | Display device and control device thereof |
US20060082701A1 (en) * | 2004-10-18 | 2006-04-20 | Tong Li | Module for liquid crystal displays |
WO2006047306A1 (en) * | 2004-10-22 | 2006-05-04 | Johnson Controls Technology Company | Lamp with emissive material outside of light source |
US7318298B2 (en) * | 2004-10-29 | 2008-01-15 | Cosco Management, Inc. | Illuminated security gate unit |
US7220040B2 (en) * | 2004-11-12 | 2007-05-22 | Harris Corporation | LED light engine for backlighting a liquid crystal display |
KR101194703B1 (en) * | 2004-11-17 | 2012-10-29 | 코닌클리즈케 필립스 일렉트로닉스 엔.브이. | Light source and illumination device comprising at least one light-emitting element |
TWI315012B (en) * | 2005-01-28 | 2009-09-21 | Au Optronics Corporatio | System of backlight module and lcd using the same |
US20070045640A1 (en) * | 2005-08-23 | 2007-03-01 | Erchak Alexei A | Light emitting devices for liquid crystal displays |
WO2006096671A2 (en) * | 2005-03-08 | 2006-09-14 | Luminus Devices, Inc. | Light emitting devices for liquid crystal displays |
US20060221271A1 (en) * | 2005-04-04 | 2006-10-05 | Tsai Chen C | Structure of LCD backlight module |
JP5057692B2 (en) * | 2005-04-27 | 2012-10-24 | サムソン エルイーディー カンパニーリミテッド. | Backlight unit using light emitting diode |
EP1883855B1 (en) | 2005-05-16 | 2011-07-20 | Donnelly Corporation | Vehicle mirror assembly with indicia at reflective element |
US8215815B2 (en) * | 2005-06-07 | 2012-07-10 | Oree, Inc. | Illumination apparatus and methods of forming the same |
US8128272B2 (en) | 2005-06-07 | 2012-03-06 | Oree, Inc. | Illumination apparatus |
US8272758B2 (en) | 2005-06-07 | 2012-09-25 | Oree, Inc. | Illumination apparatus and methods of forming the same |
KR100687926B1 (en) | 2005-06-13 | 2007-02-27 | 삼성전자주식회사 | Liquid crystal display |
US9087669B2 (en) * | 2005-06-27 | 2015-07-21 | Graftech International Holdings Inc. | Display device having improved properties |
US9081220B2 (en) * | 2005-06-27 | 2015-07-14 | Graftech International Holdings Inc. | Optimized frame system for a display device |
US9104058B2 (en) * | 2005-06-27 | 2015-08-11 | Graftech International Holdings Inc. | Optimized frame system for a liquid crystal display device |
DE102005033982A1 (en) * | 2005-07-20 | 2007-02-01 | Siemens Ag | Display unit, especially for motor vehicle, has light conductor arranged at distance from circuit board so as to form free space between circuit board and light conductor |
US20070064443A1 (en) * | 2005-08-31 | 2007-03-22 | American Panel Corporation | Led backlight for flat panel display |
US20070053179A1 (en) * | 2005-09-08 | 2007-03-08 | Pang Slew I | Low profile light source utilizing a flexible circuit carrier |
US20070097066A1 (en) * | 2005-10-27 | 2007-05-03 | Ward Calvin B | LCD display utilizing light emitters with variable light output |
CN101535087B (en) | 2005-11-01 | 2013-05-15 | 唐纳利公司 | Interior rearview mirror with display |
US20070114010A1 (en) * | 2005-11-09 | 2007-05-24 | Girish Upadhya | Liquid cooling for backlit displays |
KR100722096B1 (en) * | 2005-11-23 | 2007-05-25 | 삼성에스디아이 주식회사 | Portable display device |
KR20070054825A (en) * | 2005-11-24 | 2007-05-30 | 엘지이노텍 주식회사 | Lighting apparatus with light emitting diode |
KR20090009772A (en) | 2005-12-22 | 2009-01-23 | 크리 엘이디 라이팅 솔루션즈, 인크. | Lighting device |
US7540616B2 (en) * | 2005-12-23 | 2009-06-02 | 3M Innovative Properties Company | Polarized, multicolor LED-based illumination source |
EP1969284B1 (en) * | 2005-12-27 | 2012-06-13 | Showa Denko K.K. | Flat light source device and display device using the same |
KR100813241B1 (en) * | 2006-01-13 | 2008-03-13 | 삼성에스디아이 주식회사 | Field emission type backlight unit, and manufacturing method of upper panel thereof |
EP1991905B1 (en) * | 2006-03-09 | 2011-05-11 | Gentex Corporation | Vehicle rearview assembly including a high intensity display |
KR100978045B1 (en) | 2006-03-13 | 2010-08-26 | 삼성전자주식회사 | Lyquid crystal panel assembly and lyquid crystal display having the same |
US7682850B2 (en) * | 2006-03-17 | 2010-03-23 | Philips Lumileds Lighting Company, Llc | White LED for backlight with phosphor plates |
US8513875B2 (en) * | 2006-04-18 | 2013-08-20 | Cree, Inc. | Lighting device and lighting method |
US9084328B2 (en) | 2006-12-01 | 2015-07-14 | Cree, Inc. | Lighting device and lighting method |
US7540628B2 (en) * | 2006-04-24 | 2009-06-02 | Novicomm, Inc. | Illuminated panels and methods therefor |
US7876393B2 (en) * | 2006-06-01 | 2011-01-25 | Sharp Kabushiki Kaisha | Surface-area light source and LCD device having light guide plate with a side surface having a staircase shape in which a plurality of light emitting devices are fixed to respective steps thereof |
TW200803651A (en) * | 2006-06-02 | 2008-01-01 | Chicony Electronic Co Ltd | Method of fabricating electronic module with side contact |
JP5525259B2 (en) * | 2006-06-22 | 2014-06-18 | コーニンクレッカ フィリップス エヌ ヴェ | Drive circuit that drives a load using pulse current |
US7759882B2 (en) * | 2006-07-31 | 2010-07-20 | Microsemi Corp.—Analog Mixed Signal Group Ltd. | Color control for scanning backlight |
KR20080013127A (en) * | 2006-08-07 | 2008-02-13 | 삼성전자주식회사 | Backlight unit and liquid crystal display having the same |
US7671936B2 (en) * | 2006-09-21 | 2010-03-02 | Hannstar Display Corp. | Liquid crystal display comprising at least one LED and a PCB and a frame having an opening with a narrow portion and a broad portion on a side surface of the frame and backlight module having the same |
KR20080027599A (en) * | 2006-09-25 | 2008-03-28 | 삼성전자주식회사 | Backligth assembly and display device having the same |
US7605880B2 (en) * | 2006-10-27 | 2009-10-20 | Chunghwa Picture Tubes, Ltd. | Liquid crystal display |
US9441793B2 (en) | 2006-12-01 | 2016-09-13 | Cree, Inc. | High efficiency lighting device including one or more solid state light emitters, and method of lighting |
US20080136770A1 (en) * | 2006-12-07 | 2008-06-12 | Microsemi Corp. - Analog Mixed Signal Group Ltd. | Thermal Control for LED Backlight |
TWI348142B (en) * | 2006-12-29 | 2011-09-01 | Wintek Corp | Field sequential liquid crystal display and dricing method thereof |
US7461962B2 (en) * | 2007-01-22 | 2008-12-09 | Samsung Electronics Co., Ltd. | Backlight assembly, display device provided with the same, and method thereof |
US20080186732A1 (en) * | 2007-02-03 | 2008-08-07 | Awai George K | Light emitting diode modules for illuminated panels |
KR101309171B1 (en) * | 2007-02-15 | 2013-09-17 | 삼성디스플레이 주식회사 | Light source unit and liquid crystal display comprising the same |
US20080197369A1 (en) * | 2007-02-20 | 2008-08-21 | Cree, Inc. | Double flip semiconductor device and method for fabrication |
JP5830224B2 (en) * | 2007-02-26 | 2015-12-09 | コーニンクレッカ フィリップス エヌ ヴェKoninklijke Philips N.V. | Lighting device drive |
DE102007009532A1 (en) * | 2007-02-27 | 2008-08-28 | Osram Opto Semiconductors Gmbh | Radiation-emitting semiconductor component i.e. red luminous LED, controlling method for operating component, involves generating pulse-shaped electrical operating current for operating radiation-emitting semiconductor component |
JP4305539B2 (en) * | 2007-03-20 | 2009-07-29 | カシオ計算機株式会社 | Liquid crystal display |
US8792070B2 (en) | 2007-03-21 | 2014-07-29 | Honeywell International Inc. | Polarization plate for use in a liquid crystal display |
US7548030B2 (en) * | 2007-03-29 | 2009-06-16 | Microsemi Corp.—Analog Mixed Signal Group Ltd. | Color control for dynamic scanning backlight |
KR101375851B1 (en) * | 2007-06-01 | 2014-04-01 | 엘지디스플레이 주식회사 | Liquid crystal display device |
KR101348247B1 (en) * | 2007-06-07 | 2014-01-09 | 삼성디스플레이 주식회사 | Liquid crystal display device |
US7812297B2 (en) * | 2007-06-26 | 2010-10-12 | Microsemi Corp. - Analog Mixed Signal Group, Ltd. | Integrated synchronized optical sampling and control element |
US20090015748A1 (en) * | 2007-07-10 | 2009-01-15 | Nec Lcd Technologies, Ltd | Liquid crystal display device |
TW200924625A (en) | 2007-08-07 | 2009-06-01 | Cooligy Inc | Deformable duct guides that accommodate electronic connection lines |
CN101408290A (en) * | 2007-10-11 | 2009-04-15 | 富士迈半导体精密工业(上海)有限公司 | LED lighting device |
TW200921207A (en) * | 2007-11-06 | 2009-05-16 | Ind Tech Res Inst | Light-emitting module |
US9431589B2 (en) * | 2007-12-14 | 2016-08-30 | Cree, Inc. | Textured encapsulant surface in LED packages |
US8182128B2 (en) * | 2007-12-19 | 2012-05-22 | Oree, Inc. | Planar white illumination apparatus |
US7907804B2 (en) * | 2007-12-19 | 2011-03-15 | Oree, Inc. | Elimination of stitch artifacts in a planar illumination area |
US8104945B2 (en) * | 2007-12-27 | 2012-01-31 | Samsung Led Co., Ltd. | Backlight unit implementing local dimming for liquid crystal display device |
KR20090074478A (en) * | 2008-01-02 | 2009-07-07 | 삼성전자주식회사 | Light source module for display device and display device having the same |
CN101932872B (en) * | 2008-02-01 | 2012-06-27 | 可乐丽股份有限公司 | Surface light source element and image display device provided with the surface light source element |
CN101978297A (en) * | 2008-03-05 | 2011-02-16 | 奥利高级照明解决公司 | Illumination apparatus and methods of forming the same |
WO2009113055A2 (en) * | 2008-03-13 | 2009-09-17 | Microsemi Corp. - Analog Mixed Signal Group, Ltd. | A color controller for a luminaire |
US8154418B2 (en) | 2008-03-31 | 2012-04-10 | Magna Mirrors Of America, Inc. | Interior rearview mirror system |
US8085359B2 (en) * | 2008-04-16 | 2011-12-27 | Honeywell International Inc. | Folded backlight systems having low index regions that prevent light failing to meet total internal reflection conditions from entering a plate portion and liquid crystal displays using the same |
US8028537B2 (en) * | 2009-05-01 | 2011-10-04 | Abl Ip Holding Llc | Heat sinking and flexible circuit board, for solid state light fixture utilizing an optical cavity |
US8021008B2 (en) * | 2008-05-27 | 2011-09-20 | Abl Ip Holding Llc | Solid state lighting using quantum dots in a liquid |
US8994615B2 (en) * | 2008-06-06 | 2015-03-31 | Dolby Laboratories Licensing Corporation | Apparatus and methods for driving solid-state illumination sources |
TW201004477A (en) * | 2008-06-10 | 2010-01-16 | Microsemi Corp Analog Mixed Si | Color manager for backlight systems operative at multiple current levels |
TWM351370U (en) * | 2008-07-02 | 2009-02-21 | Chunghwa Picture Tubes Ltd | Backlight module |
KR101274709B1 (en) * | 2008-07-08 | 2013-06-12 | 엘지디스플레이 주식회사 | Liquid crystal display |
US8301002B2 (en) * | 2008-07-10 | 2012-10-30 | Oree, Inc. | Slim waveguide coupling apparatus and method |
US8297786B2 (en) * | 2008-07-10 | 2012-10-30 | Oree, Inc. | Slim waveguide coupling apparatus and method |
US8547321B2 (en) * | 2008-07-23 | 2013-10-01 | Apple Inc. | LED backlight driver synchronization and power reduction |
JP5261056B2 (en) * | 2008-07-28 | 2013-08-14 | パナソニック株式会社 | Backlight device |
US8582052B2 (en) * | 2008-08-22 | 2013-11-12 | Gentex Corporation | Discrete LED backlight control for a reduced power LCD display system |
KR101502420B1 (en) * | 2008-09-22 | 2015-03-25 | 삼성디스플레이 주식회사 | Light source module and display device having the same |
US9487144B2 (en) | 2008-10-16 | 2016-11-08 | Magna Mirrors Of America, Inc. | Interior mirror assembly with display |
US9262958B2 (en) | 2008-11-06 | 2016-02-16 | E.F. Johnson Company | Control head with electroluminescent panel in land mobile radio |
US20100109562A1 (en) * | 2008-11-06 | 2010-05-06 | StarChips Technology Inc. | Backlight module and light-emitting device thereof |
DE102008057347A1 (en) | 2008-11-14 | 2010-05-20 | Osram Opto Semiconductors Gmbh | Optoelectronic device |
WO2010059579A1 (en) * | 2008-11-19 | 2010-05-27 | 3M Innovative Properties Company | High transmission flux leveling multilayer optical film and related constructions |
US9326346B2 (en) | 2009-01-13 | 2016-04-26 | Terralux, Inc. | Method and device for remote sensing and control of LED lights |
US8358085B2 (en) | 2009-01-13 | 2013-01-22 | Terralux, Inc. | Method and device for remote sensing and control of LED lights |
BRPI1005305A2 (en) | 2009-01-28 | 2019-09-24 | Koninl Philips Electronics Nv | lighting system, remote phosphor layer. scatter layer, luminaire, display device and method of correcting at least partially a light-emitting characteristic from at least one light source in a lighting system |
US20100208470A1 (en) * | 2009-02-10 | 2010-08-19 | Yosi Shani | Overlapping illumination surfaces with reduced linear artifacts |
US20100214282A1 (en) | 2009-02-24 | 2010-08-26 | Dolby Laboratories Licensing Corporation | Apparatus for providing light source modulation in dual modulator displays |
EP2228257A1 (en) * | 2009-03-13 | 2010-09-15 | Alfred Held | Light device and method of assembling a light device |
US8624527B1 (en) | 2009-03-27 | 2014-01-07 | Oree, Inc. | Independently controllable illumination device |
US8096671B1 (en) | 2009-04-06 | 2012-01-17 | Nmera, Llc | Light emitting diode illumination system |
JP2010243825A (en) * | 2009-04-07 | 2010-10-28 | Hitachi Displays Ltd | Liquid crystal display |
KR100966874B1 (en) | 2009-04-27 | 2010-06-29 | 삼성전자주식회사 | Back light assembly and liquid crystal display comprising the same |
KR20100121861A (en) * | 2009-05-11 | 2010-11-19 | 삼성전자주식회사 | Light emitting unit and back light unit having the same |
US20100320904A1 (en) * | 2009-05-13 | 2010-12-23 | Oree Inc. | LED-Based Replacement Lamps for Incandescent Fixtures |
WO2010150202A2 (en) | 2009-06-24 | 2010-12-29 | Oree, Advanced Illumination Solutions Inc. | Illumination apparatus with high conversion efficiency and methods of forming the same |
TWI417615B (en) * | 2009-07-07 | 2013-12-01 | Chi Lin Optoelectronics Co Ltd | Edge light type backlight module |
BR112012011829A2 (en) | 2009-11-17 | 2018-03-27 | Terralux Inc | led power supply detection and control |
US8836888B2 (en) * | 2009-12-15 | 2014-09-16 | Gentex Corporation | Modular light source/electronics and automotive rearview assemblies using the same |
WO2011086790A1 (en) * | 2010-01-18 | 2011-07-21 | シャープ株式会社 | Lighting device, display apparatus, and television receiver apparatus |
KR101047628B1 (en) * | 2010-06-03 | 2011-07-08 | 엘지이노텍 주식회사 | A backlight unit and a display apparatus |
WO2012037436A1 (en) | 2010-09-16 | 2012-03-22 | Terralux, Inc. | Communication with lighting units over a power bus |
US9596738B2 (en) | 2010-09-16 | 2017-03-14 | Terralux, Inc. | Communication with lighting units over a power bus |
TWI471504B (en) * | 2010-10-27 | 2015-02-01 | Young Lighting Technology Corp | Flat light source module |
TWI407199B (en) * | 2010-10-29 | 2013-09-01 | Au Optronics Corp | Flat panel display structure and manufacturing method thereof |
US20120113675A1 (en) * | 2010-11-05 | 2012-05-10 | Lextar Electronics Corporation | Lamp device with color-changeable filter |
TWI472704B (en) * | 2010-11-05 | 2015-02-11 | Lextar Electronics Corp | Lamp device with color-changeable filter |
JP5527230B2 (en) * | 2011-01-21 | 2014-06-18 | 株式会社Jvcケンウッド | Backlight device and image display device |
US9274269B2 (en) | 2011-05-31 | 2016-03-01 | Lg Innotek Co., Ltd. | Backlight unit and display device |
KR101808191B1 (en) * | 2011-08-26 | 2017-12-13 | 삼성전자 주식회사 | A Backlight Unit and A Liquid Crystal Display having the Backlight Unit |
JP2013050470A (en) * | 2011-08-30 | 2013-03-14 | Funai Electric Co Ltd | Thin display device |
KR101251815B1 (en) * | 2011-11-07 | 2013-04-09 | 엘지이노텍 주식회사 | Optical sheet and display device having the same |
US8591072B2 (en) | 2011-11-16 | 2013-11-26 | Oree, Inc. | Illumination apparatus confining light by total internal reflection and methods of forming the same |
US9244299B2 (en) * | 2011-11-22 | 2016-01-26 | Shenzhen China Star Optoelectronics Technology Co., Ltd. | Backlight module of display device |
WO2013090904A1 (en) | 2011-12-16 | 2013-06-20 | Terralux, Inc. | System and methods of applying bleed circuits in led lamps |
CN102620194A (en) * | 2012-03-12 | 2012-08-01 | 深圳市华星光电技术有限公司 | Backlight module and liquid crystal display device |
US20130258708A1 (en) * | 2012-04-01 | 2013-10-03 | Shenzhen China str Optoelectronics Technology Co., LTD. | Backlight Module |
JP2013218125A (en) * | 2012-04-10 | 2013-10-24 | Japan Display Inc | Liquid-crystal display |
US8879139B2 (en) | 2012-04-24 | 2014-11-04 | Gentex Corporation | Display mirror assembly |
US20130328942A1 (en) * | 2012-06-12 | 2013-12-12 | Stephen Chen | Head up display for a vehicle |
WO2014006501A1 (en) | 2012-07-03 | 2014-01-09 | Yosi Shani | Planar remote phosphor illumination apparatus |
DE102012212557A1 (en) * | 2012-07-18 | 2014-01-23 | Osram Opto Semiconductors Gmbh | Device for providing electromagnetic radiation for illumination device e.g. LED of headlight for motor car, has uncoupling region that deflects striking beam paths of electromagnetic radiation in direction out of beam guide |
US9353917B2 (en) | 2012-09-14 | 2016-05-31 | Cree, Inc. | High efficiency lighting device including one or more solid state light emitters, and method of lighting |
US9207484B2 (en) * | 2012-09-26 | 2015-12-08 | Apple Inc. | Computer LED bar and thermal architecture features |
US9558721B2 (en) | 2012-10-15 | 2017-01-31 | Apple Inc. | Content-based adaptive refresh schemes for low-power displays |
CN103032766A (en) * | 2012-12-12 | 2013-04-10 | 京东方科技集团股份有限公司 | Backlight module and display device |
US9153171B2 (en) | 2012-12-17 | 2015-10-06 | LuxVue Technology Corporation | Smart pixel lighting and display microcontroller |
US20140204309A1 (en) * | 2013-01-24 | 2014-07-24 | Kabushiki Kaisha Toshiba | Electronic apparatus |
KR101881346B1 (en) | 2013-03-15 | 2018-07-24 | 젠텍스 코포레이션 | Display mirror assembly |
EP2790470B1 (en) | 2013-04-08 | 2018-03-21 | Dialog Semiconductor GmbH | Programmable current source with optimized compliance region for efficient backlighting in portable applications |
US9179554B2 (en) * | 2013-04-09 | 2015-11-03 | Whirlpool Corporation | Appliance displays having modular light guides and methods of assembling the same |
CN104241262B (en) | 2013-06-14 | 2020-11-06 | 惠州科锐半导体照明有限公司 | Light emitting device and display device |
US9265119B2 (en) | 2013-06-17 | 2016-02-16 | Terralux, Inc. | Systems and methods for providing thermal fold-back to LED lights |
AU2014326772B2 (en) | 2013-09-24 | 2017-07-20 | Gentex Corporation | Display mirror assembly |
KR102148718B1 (en) * | 2013-12-18 | 2020-08-27 | 삼성전자주식회사 | Display device |
WO2015116915A1 (en) | 2014-01-31 | 2015-08-06 | Gentex Corporation | Backlighting assembly for display for reducing cross-hatching |
EP3119643B1 (en) | 2014-03-21 | 2018-05-23 | Gentex Corporation | Tri-modal display mirror assembly |
TWI588572B (en) * | 2014-03-31 | 2017-06-21 | 瑞儀光電股份有限公司 | Light source assembly |
US9834146B2 (en) | 2014-04-01 | 2017-12-05 | Gentex Corporation | Automatic display mirror assembly |
US9741286B2 (en) | 2014-06-03 | 2017-08-22 | Apple Inc. | Interactive display panel with emitting and sensing diodes |
US9570002B2 (en) | 2014-06-17 | 2017-02-14 | Apple Inc. | Interactive display panel with IR diodes |
US20160031462A1 (en) * | 2014-07-29 | 2016-02-04 | Electro-Motive Diesel, Inc. | Apparatus for displaying road number for a locomotive |
TWI526505B (en) | 2014-09-11 | 2016-03-21 | 財團法人工業技術研究院 | Hardcoat composition and polarizer and display device applying the same |
US9694751B2 (en) | 2014-09-19 | 2017-07-04 | Gentex Corporation | Rearview assembly |
US9694752B2 (en) | 2014-11-07 | 2017-07-04 | Gentex Corporation | Full display mirror actuator |
EP3218227B1 (en) | 2014-11-13 | 2018-10-24 | Gentex Corporation | Rearview mirror system with a display |
KR101997815B1 (en) | 2014-12-03 | 2019-07-08 | 젠텍스 코포레이션 | Display mirror assembly |
USD746744S1 (en) | 2014-12-05 | 2016-01-05 | Gentex Corporation | Rearview device |
US9744907B2 (en) | 2014-12-29 | 2017-08-29 | Gentex Corporation | Vehicle vision system having adjustable displayed field of view |
WO2016111492A1 (en) * | 2015-01-05 | 2016-07-14 | Samsung Electronics Co., Ltd. | Display module and display apparatus having the same |
US9720278B2 (en) | 2015-01-22 | 2017-08-01 | Gentex Corporation | Low cost optical film stack |
KR102318262B1 (en) | 2015-03-11 | 2021-10-27 | 삼성디스플레이 주식회사 | Backlight unit and display device comprising the same |
US9501174B2 (en) * | 2015-04-10 | 2016-11-22 | Apple Inc. | Temperature sensing display assemblies |
CN107531183B (en) | 2015-04-20 | 2021-09-03 | 金泰克斯公司 | Rearview assembly with applique |
US10247870B2 (en) * | 2015-05-04 | 2019-04-02 | Himax Display, Inc. | Wearable display apparatus comprising an optical assembly having an optical integrator rod |
JP6526243B2 (en) | 2015-05-18 | 2019-06-05 | ジェンテックス コーポレイション | Full screen display rearview mirror device |
CN107709096B (en) | 2015-06-22 | 2021-08-24 | 金泰克斯公司 | System and method for processing streaming video images to correct for flicker of amplitude modulated light |
JP6680868B2 (en) | 2015-08-17 | 2020-04-15 | インフィニット アースロスコピー インコーポレーテッド, リミテッド | light source |
USD798207S1 (en) | 2015-10-30 | 2017-09-26 | Gentex Corporation | Rearview mirror assembly |
EP3368375B1 (en) | 2015-10-30 | 2020-03-04 | Gentex Corporation | Rearview device |
US10685623B2 (en) | 2015-10-30 | 2020-06-16 | Gentex Corporation | Toggle paddle |
USD797627S1 (en) | 2015-10-30 | 2017-09-19 | Gentex Corporation | Rearview mirror device |
USD800618S1 (en) | 2015-11-02 | 2017-10-24 | Gentex Corporation | Toggle paddle for a rear view device |
WO2017087448A1 (en) | 2015-11-16 | 2017-05-26 | Infinite Arthroscopy Inc, Limited | Wireless medical imaging system |
US20200262351A1 (en) * | 2015-12-17 | 2020-08-20 | 3M Innovative Properties Company | Mirror including reflective backlit display |
US11274823B1 (en) | 2016-03-02 | 2022-03-15 | Cooledge Lighting, Inc. | Lighting systems incorporating connections for signal and power transmission |
US10746358B1 (en) | 2016-03-02 | 2020-08-18 | Cooledge Lighting Inc. | Lighting systems incorporating connections for signal and power transmission |
US10344954B1 (en) | 2016-03-02 | 2019-07-09 | Cooledge Lighting Inc. | Lighting systems incorporating connections for signal and power transmission |
USD845851S1 (en) | 2016-03-31 | 2019-04-16 | Gentex Corporation | Rearview device |
USD817238S1 (en) | 2016-04-29 | 2018-05-08 | Gentex Corporation | Rearview device |
US10025138B2 (en) | 2016-06-06 | 2018-07-17 | Gentex Corporation | Illuminating display with light gathering structure |
KR102605921B1 (en) * | 2016-09-27 | 2023-11-27 | 삼성디스플레이 주식회사 | Backlight unit and display apparatus including the same |
US10288797B1 (en) * | 2016-10-24 | 2019-05-14 | Amazon Technologies, Inc. | Structural alignment features for light emitting diode arrays |
CN106491039B (en) * | 2016-11-14 | 2019-01-08 | 浙江工业大学 | A kind of swing type window wiping robot glass edge detection method |
CN106491042B (en) * | 2016-11-14 | 2019-01-08 | 浙江工业大学 | Processing method is moved down at a kind of swing type window wiping robot glass edge |
USD809984S1 (en) | 2016-12-07 | 2018-02-13 | Gentex Corporation | Rearview assembly |
USD854473S1 (en) | 2016-12-16 | 2019-07-23 | Gentex Corporation | Rearview assembly |
WO2018125898A1 (en) | 2016-12-30 | 2018-07-05 | Gentex Corporation | Full display mirror with on-demand spotter view |
WO2018152196A1 (en) | 2017-02-15 | 2018-08-23 | Infinite Arthroscopy Inc. Limited | Wireless medical imaging system comprising a head unit and a light cable that comprises an integrated light source |
CN110325787B (en) * | 2017-03-02 | 2022-05-17 | 昕诺飞控股有限公司 | Luminaire with light guide |
CN110382205B (en) | 2017-03-09 | 2021-10-22 | 昕诺飞控股有限公司 | Core-shell filament for printing smooth FDM 3D articles |
JP7203366B2 (en) * | 2017-03-16 | 2023-01-13 | パナソニックIpマネジメント株式会社 | Display device |
EP3595931A4 (en) | 2017-03-17 | 2020-01-22 | Gentex Corporation | Dual display reverse camera system |
US10429574B2 (en) * | 2017-06-30 | 2019-10-01 | Wuhan China Star Optoelectronics Technology Co., Ltd. | Liquid crystal display and backlight module thereof |
KR101977261B1 (en) * | 2017-11-03 | 2019-05-13 | 엘지전자 주식회사 | Phosphor module |
USD938584S1 (en) | 2020-03-30 | 2021-12-14 | Lazurite Holdings Llc | Hand piece |
USD972176S1 (en) | 2020-08-06 | 2022-12-06 | Lazurite Holdings Llc | Light source |
CN113156703A (en) * | 2021-04-22 | 2021-07-23 | 深圳市华星光电半导体显示技术有限公司 | Backlight module and quantum dot display device |
EP4388243A1 (en) | 2021-08-20 | 2024-06-26 | Gentex Corporation | Lighting assembly and illumination system having a lighting assembly |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH087614A (en) * | 1994-06-17 | 1996-01-12 | Nichia Chem Ind Ltd | Sheet-like light source |
JPH1153920A (en) * | 1997-07-31 | 1999-02-26 | Sanyo Electric Co Ltd | Light-emitting device and led light emitter |
JP2000267606A (en) * | 1999-03-19 | 2000-09-29 | Toshiba Corp | Light source and video display device |
Family Cites Families (44)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3925690A (en) | 1974-09-30 | 1975-12-09 | Rockwell International Corp | Direct drive circuit for light emitting diodes |
CH604258B5 (en) * | 1976-04-02 | 1978-08-31 | Ebauches Sa | |
US4090189A (en) | 1976-05-20 | 1978-05-16 | General Electric Company | Brightness control circuit for LED displays |
US4160934A (en) | 1977-08-11 | 1979-07-10 | Bell Telephone Laboratories, Incorporated | Current control circuit for light emitting diode |
JP2749012B2 (en) * | 1987-08-28 | 1998-05-13 | 株式会社日立製作所 | Liquid crystal display |
US4959642A (en) | 1988-09-27 | 1990-09-25 | Sharples Kenneth R | Instrumentation loop-powered backlit liquid crystal display |
US5105179A (en) | 1990-06-28 | 1992-04-14 | Smith J Wise | Electronic display license plate |
US5528720A (en) | 1992-03-23 | 1996-06-18 | Minnesota Mining And Manufacturing Co. | Tapered multilayer luminaire devices |
US5422756A (en) | 1992-05-18 | 1995-06-06 | Minnesota Mining And Manufacturing Company | Backlighting system using a retroreflecting polarizer |
US5359691A (en) | 1992-10-08 | 1994-10-25 | Briteview Technologies | Backlighting system with a multi-reflection light injection system and using microprisms |
US5390276A (en) | 1992-10-08 | 1995-02-14 | Briteview Technologies | Backlighting assembly utilizing microprisms and especially suitable for use with a liquid crystal display |
JPH06242441A (en) | 1992-12-22 | 1994-09-02 | Canon Inc | Light source device and display device equipped with the same |
US6084519A (en) | 1993-05-07 | 2000-07-04 | Control Devices, Inc. | Multi-function light sensor for vehicle |
US6025897A (en) * | 1993-12-21 | 2000-02-15 | 3M Innovative Properties Co. | Display with reflective polarizer and randomizing cavity |
US5828488A (en) | 1993-12-21 | 1998-10-27 | Minnesota Mining And Manufacturing Co. | Reflective polarizer display |
JP3219943B2 (en) * | 1994-09-16 | 2001-10-15 | 株式会社東芝 | Planar direct-view display device |
US5751388A (en) * | 1995-04-07 | 1998-05-12 | Honeywell Inc. | High efficiency polarized display |
WO1997001788A1 (en) | 1995-06-26 | 1997-01-16 | Minnesota Mining And Manufacturing Company | Transflective displays with reflective polarizing transflector |
US5924784A (en) | 1995-08-21 | 1999-07-20 | Chliwnyj; Alex | Microprocessor based simulated electronic flame |
US5889568A (en) * | 1995-12-12 | 1999-03-30 | Rainbow Displays Inc. | Tiled flat panel displays |
JP3319279B2 (en) * | 1996-04-23 | 2002-08-26 | セイコーエプソン株式会社 | Liquid crystal display |
KR100537349B1 (en) * | 1996-06-26 | 2006-02-28 | 오스람 게젤샤프트 미트 베쉬랭크터 하프퉁 | Light-emitting semiconductor component with luminescence conversion element |
KR19990044363A (en) | 1996-07-09 | 1999-06-25 | 오오시마 야스히로 | Exposure apparatus, exposure method and printing apparatus |
TW383508B (en) * | 1996-07-29 | 2000-03-01 | Nichia Kagaku Kogyo Kk | Light emitting device and display |
JP3466433B2 (en) * | 1996-11-12 | 2003-11-10 | シャープ株式会社 | Liquid crystal display |
JP3881701B2 (en) * | 1997-05-14 | 2007-02-14 | セイコーエプソン株式会社 | Display device and electronic apparatus using the same |
US6150771A (en) | 1997-06-11 | 2000-11-21 | Precision Solar Controls Inc. | Circuit for interfacing between a conventional traffic signal conflict monitor and light emitting diodes replacing a conventional incandescent bulb in the signal |
GB2328591B (en) | 1997-08-21 | 2003-03-05 | Comm & Control Electronics Ltd | Local communication system and apparatus for use therein |
JP3460588B2 (en) * | 1997-09-18 | 2003-10-27 | セイコーエプソン株式会社 | Display device and electronic device using the same |
US6069448A (en) | 1997-10-16 | 2000-05-30 | Twinhead International Corp. | LCD backlight converter having a temperature compensating means for regulating brightness |
US6497946B1 (en) * | 1997-10-24 | 2002-12-24 | 3M Innovative Properties Company | Diffuse reflective articles |
US5976686A (en) * | 1997-10-24 | 1999-11-02 | 3M Innovative Properties Company | Diffuse reflective articles |
US6107985A (en) | 1997-10-30 | 2000-08-22 | Ericsson Inc. | Backlighting circuits including brownout detection circuits responsive to a current through at least one light emitting diode and related methods |
JP3047885B2 (en) | 1998-04-09 | 2000-06-05 | 日本電気株式会社 | Backlight control device and backlight control method |
JP3114805B2 (en) * | 1998-04-15 | 2000-12-04 | 日亜化学工業株式会社 | Planar light source, display backlight using the same, and illuminated operation switch |
JP3280307B2 (en) | 1998-05-11 | 2002-05-13 | インターナショナル・ビジネス・マシーンズ・コーポレーション | Liquid crystal display |
JP3594500B2 (en) * | 1998-11-12 | 2004-12-02 | 松下電器産業株式会社 | LCD display mounting connection device |
US6351069B1 (en) * | 1999-02-18 | 2002-02-26 | Lumileds Lighting, U.S., Llc | Red-deficiency-compensating phosphor LED |
US6351079B1 (en) | 1999-08-19 | 2002-02-26 | Schott Fibre Optics (Uk) Limited | Lighting control device |
TW500962B (en) * | 1999-11-26 | 2002-09-01 | Sanyo Electric Co | Surface light source and method for adjusting its hue |
US6437469B1 (en) * | 2000-09-25 | 2002-08-20 | Aaon, Inc. | Heat dissipating collar for motor |
US6411046B1 (en) | 2000-12-27 | 2002-06-25 | Koninklijke Philips Electronics, N. V. | Effective modeling of CIE xy coordinates for a plurality of LEDs for white LED light control |
US6717559B2 (en) * | 2001-01-16 | 2004-04-06 | Visteon Global Technologies, Inc. | Temperature compensated parallel LED drive circuit |
US6697130B2 (en) * | 2001-01-16 | 2004-02-24 | Visteon Global Technologies, Inc. | Flexible led backlighting circuit |
-
2001
- 2001-12-28 US US10/040,864 patent/US6930737B2/en not_active Expired - Lifetime
-
2002
- 2002-01-14 DE DE10201052A patent/DE10201052B8/en not_active Expired - Lifetime
- 2002-01-14 GB GB0200653A patent/GB2374714B/en not_active Expired - Fee Related
-
2005
- 2005-03-23 US US11/089,211 patent/US7193248B2/en not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH087614A (en) * | 1994-06-17 | 1996-01-12 | Nichia Chem Ind Ltd | Sheet-like light source |
JPH1153920A (en) * | 1997-07-31 | 1999-02-26 | Sanyo Electric Co Ltd | Light-emitting device and led light emitter |
JP2000267606A (en) * | 1999-03-19 | 2000-09-29 | Toshiba Corp | Light source and video display device |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP1533851A2 (en) * | 2003-11-20 | 2005-05-25 | Sumitomo Electric Industries, Ltd. | Light-emitting diode and semiconductor light-emitting device |
EP1533851A3 (en) * | 2003-11-20 | 2010-05-26 | Sumitomo Electric Industries, Ltd. | Light-emitting diode and semiconductor light-emitting device |
GB2428859A (en) * | 2005-08-01 | 2007-02-07 | Avago Technologies General Ip | Light source and apparatus including a light source |
GB2443754A (en) * | 2005-08-01 | 2008-05-14 | Avago Technologies General Ip | Apparatus including a light source and a light pipe |
GB2446978A (en) * | 2005-08-01 | 2008-08-27 | Avago Technologies General Ip | Apparatus including a light source and a light pipe |
GB2443754B (en) * | 2005-08-01 | 2008-10-15 | Avago Technologies General Ip | Light source and apparatus including a light source |
GB2428859B (en) * | 2005-08-01 | 2008-10-15 | Avago Technologies General Ip | Light source and apparatus including a light source |
GB2446978B (en) * | 2005-08-01 | 2008-10-15 | Avago Technologies General Ip | Light source and apparatus including a light source |
US7513669B2 (en) | 2005-08-01 | 2009-04-07 | Avago Technologies General Ip (Singapore) Pte. Ltd. | Light source for LCD back-lit displays |
Also Published As
Publication number | Publication date |
---|---|
GB0200653D0 (en) | 2002-02-27 |
US6930737B2 (en) | 2005-08-16 |
GB2374714B (en) | 2003-04-09 |
DE10201052B8 (en) | 2012-04-19 |
DE10201052B4 (en) | 2011-12-15 |
US20020140880A1 (en) | 2002-10-03 |
US20050185113A1 (en) | 2005-08-25 |
US7193248B2 (en) | 2007-03-20 |
DE10201052A1 (en) | 2002-08-01 |
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PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 20060114 |